Land of contradictions
The United States means many different and often contradictory things to different people. Depending upon your point of view, the U.S. is either the trend-setter of popular culture worldwide, the source of what is newest and most exciting, or it is a cultural menace, sweeping away traditional values and customs with its exported tastes for fast food, loud music, and violence.

Global presence and the American experience
To many it is first and foremost a superpower. Some see it as exerting its might in the interest of world peace and stability, and as a guarantor of the freedom and even survival of other nations. To others, it looks more like a bully imposing its will upon the entire planet by brute force.

Above all, the American experience is defined by a fierce streak of independence, beginning with its struggle against England and continuing through the Civil War, fought to ensure the freedom of all Americans. The role of peacekeeper and mediator has become one that is familiar to the U.S., especially in recent years but is often an uneasy position on the world stage.

Diversity, change, improvement, experimentation, progress - all are important watchwords in the U.S. More than a century and a half have passed, and millions of immigrants from every continent have arrived in the U.S., choosing to stay and share in the American experience.

Diversity
The United States of America is the third most populous and the fourth largest nation in the world. A nation of immigrants, the United States continues to be predominantly populated by those of European descent accounting for approximately three-fourths of the population. However, the country's Asian and Hispanic populations are the fastest growing groups in recent years. Ethnic diversity remains a defining characteristic of the country.

Diversity also describes the vast country's landscape that ranges from charming villages and farming communities to sprawling metropolises, from the deserts of the southwest to the swamps of the southeast, and from the mountain ranges of the northwest to the flatlands of the midwest.

Culture
As with almost everything else about the United States, its culture is an amalgam of elements from many foreign sources. An initially British heritage has been enriched and expanded over more than three centuries by contributions from every continent and virtually every other country in the world, developing into a richly multifaceted and uniquely American contribution to civilization. Although a Shakespeare has yet to appear, American literature otherwise is on a par with that of Britain itself in the English-speaking world. After World War II, New York succeeded Paris as the capital of the art world. The syncopated rhythms brought from Africa by slaves became jazz, a new form of musical expression that spread from the American South throughout the country and to the world beyond.

In popular culture, the American presence is even more apparent. From fashion to fast food, American tastes influence the world. Blue jeans are au courant from Paris to Bangkok. McDonald's restaurants serve Big Macs across Europe and Asia. Hollywood films dominate world screens to the extent that some countries seek to limit their distribution.

Geography
The fourth largest nation in the world, the United States occupies 40 percent of the North American continent as well as several island territories. At its widest point, the country is 4,517 km/2,807 mi. from east to west. North to south, the maximum distance is 2,571 km/1,598 mi.

Borders
The U.S. mainland is bounded on the east by the Atlantic Ocean and on the west by the Pacific Ocean. The northern boundary, with Canada, is formed in part by the St. Lawrence River and the Great Lakes, and has been called "the longest unfortified international border in the world." On the south, the mainland is bounded by the Gulf of Mexico and, on land, by Mexico. For much of its length, the southern border follows the Rio Grande River.

States
The U.S. mainland consists of the 48 contiguous states south of Canada plus the state of Alaska, separated from the others by the Canadian province of British Columbia. Offshore are the state of Hawaii and the dependencies of Guam, American Samoa, Wake, Midway, and several smaller islands and atolls, all in the Pacific Ocean. Also associated with the U.S. are the Commonwealth of the Northern Mariana Islands, the Federated States of Micronesia, and the Republic of the Marshall Islands. The island chain of Palau is administered by the U.S. under a United Nations trusteeship. The self-governing dependencies of Puerto Rico and the Virgin Islands are located in the Atlantic Ocean.

Geographic regions of the U.S. mainland
The U.S. mainland consists of four major regions according to their distinctive natural features:

To the east and south is the Atlantic and Gulf Coastal Plain, narrow and deeply eroded at the northern end and widening to the south, becoming a broad and partly swampy lowland. Through it run many rivers ending in estuaries that have been developed as deep-sea harbors. The low, flat Florida peninsula is the southernmost extension of the plain.

To the west, the Coastal Plain is bordered by the Appalachian Highland, consisting for the most part of an ancient chain of mountains that, except in the New England states of Vermont and New Hampshire, are now relatively low. It is a watershed, with rivers on the eastern side emptying into the Atlantic and those on the western side forming part of the vast Mississippi River system.

West of the Appalachian Highland lie the great Interior Plains, a region containing about half the territory of the U.S. mainland and encompassing the drainage basin of the Mississippi River and its numerous tributaries. This is the country's principal agricultural region. To the east of the Mississippi, it is well irrigated; but to the west, it becomes increasingly arid as the central lowlands give way to the Great Plains extending to the foothills of the Rocky Mountains. From north to south, the plains region extends from the Canadian border to the Gulf of Mexico, merging with the Coastal Plain west of the Mississippi River.

The rugged Rockies are the dominant feature of the last great region, the Cordillera, which includes several other mountain chains such as the mountain-ringed Colorado Plateau, the Great Basin of Utah, the Central Valley in California, and finally the Pacific coast with the slopes of the last mountains, the Coast Range, plunging steeply to the sea in many places. Covering the westernmost quarter of the nation, the Cordillera extends north to south from the Canadian to Mexican borders. In striking contrast to the U.S. Atlantic coast, there are few good harbors along the Pacific. Puget Sound, on which Seattle is located, and San Francisco Bay are the most notable.

Alaska and Hawaii
The two outlying states, Alaska and Hawaii, have their own distinctive geographic features. Alaska, virtually a subcontinent in its own right, has a deeply indented coastline edging a vast and rugged interior of mountains and tundra. The mountainous Hawaiian archipelago was formed by volcanic activity and contains several still-active peaks, including Kilauea on the island of Hawaii which has the world's largest crater. The largest island comprising two-thirds of the chain's total territory, Hawaii is actually the peak of a gigantic submerged mountain.

Rivers
Major U.S. rivers include the Hudson, Delaware, Susquehanna, Potomac, James, and Savannah in the east; the mighty Mississippi, with the Missouri, Ohio, Tennessee, Red, and Platte among its many tributaries, in the central plains; the Rio Grande in the southwest; the Columbia and Colorado in the mountain west; and the Yukon in Alaska.